Quick connect fluid conduit couplings for conduits containing, inter alia, fuel, hydraulic fluid, or air conditioning fluids are often employed in the manufacture of automobiles to permit the rapid connection of various components and subassemblies of an automobile during final assembly. Such fluid conduit couplings are required to lock together and to have high resistance to separation caused by internal pressure, temperature, or impact It is desireable that the fluid conduit coupling be connected together without special tools or sealants, i.e., it must snap together. It is also desireable that the coupling be disconnected manually without special tools. In addition, the fluid conduit coupling must be capable of several connection/disconnection cycles. It is also desireable that such a fluid conduit coupling have a redundant lock feature in case the primary lock fails or is not made.
Various designs for quick connect fluid conduit couplings have been proposed. U.S. Pat. No. 4,055,359 to McWethy discloses one such quick connect coupling, in which a cage containing a garter spring is located around a male coupling, and which receives the flared end of a female coupling when the male and female couplings are fitted together. The garter spring slips over the flared end and prevents the coupling from being pulled apart by locating against the cage. However, the McWethy fluid conduit coupling structure requires a special annular tool to disconnect the coupling, and further, has no redundant safety lock.
U.S. Pat. No. 4,691,943 to DeLand discloses a quick connect coupling in which a female coupling has a cage extending from its end. The cage contains barbs which extend inwardly and towards the female coupling. A male coupling fits inside the cage and has protruberances which are engaged by the barbs. Deland also requires an annular tool to disconnect the coupling, and lacks a redundant safety lock.